Wafer-to-wafer (W2W) bonding is deployed in a wide range of semiconductor process applications for forming semiconductor devices. Examples of semiconductor process applications where wafer-to-wafer bonding is applied include substrate engineering and fabrication of integrated circuits, packaging and encapsulation of micro-electro-mechanical-systems (MEMS) and stacking of many processed layers (3D-integration) of pure microelectronics. W2W bonding involves aligning two or more wafer surfaces, bringing them in contact and forming a strong bond interface between them. The overall processing yield and manufacturing cost of the so produced semiconductor devices and ultimately the cost of the electronic products that incorporate these devices depend greatly upon the quality of the wafer-to-wafer bond. The quality of the W2W bond depends upon the accurate alignment of the wafers, the preservation of the wafer alignment across the wafer bond interfaces, and the uniformity and integrity of the bond strength across the wafer bond interfaces. In particular, the leveling, planarity, distance and tension between the wafer surfaces are critical to the bond quality. Accordingly, it is desirable to provide a reliable, high precision, and repeatable positioning of the semiconductor wafer surfaces relative to each other in the wafer bonder apparatus.